Faster implementation of integer-to-ascii conversion. I think....

src/heap.cc

 // Copyright 2009 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1768 matching lines @@
 
 Object* Heap::NumberToString(Object* number) {
   Object* cached = GetNumberStringCache(number);
   if (cached != undefined_value()) {
     return cached;
   }
 
   char arr[100];
   Vector<char> buffer(arr, ARRAY_SIZE(arr));
   const char* str;
+  int length = 0;
   if (number->IsSmi()) {
     int num = Smi::cast(number)->value();
-    str = IntToCString(num, buffer);
+    str = IntToCString(num, &length);
   } else {
     double num = HeapNumber::cast(number)->value();
     str = DoubleToCString(num, buffer);
+    length = strlen(str);
   }
-  Object* result = AllocateStringFromAscii(CStrVector(str));
+  Object* result = AllocateStringFromAscii(Vector<const char>(str, length));
 
   if (!result->IsFailure()) {
     SetNumberStringCache(number, String::cast(result));
   }
   return result;
 }
 
 
 Map* Heap::MapForExternalArrayType(ExternalArrayType array_type) {
   return Map::cast(roots_[RootIndexForExternalArrayType(array_type)]);
@@ skipping 2421 matching lines @@
 void ExternalStringTable::TearDown() {
   new_space_strings_.Free();
   old_space_strings_.Free();
 }
 
 
 List<Object*> ExternalStringTable::new_space_strings_;
 List<Object*> ExternalStringTable::old_space_strings_;
 
 } }  // namespace v8::internal